Category Archives: Gardening

Some insects I found inside dried Turkish figs from Trader Joe’s

During an online wasp identification course I participated in several weeks ago, there was a fun discussion about whether commercially-produced figs contained fig wasps (Agaonidae, in the Chalcidoidea). Opinions varied, plus some asserted, as do many internet pages, that even if wasps were once inside the figs that ficain (an enzyme) would completely dissolve their bodies. So I purchased a bag of figs and had a look. I found a wasp in the very first fig, in approximately two seconds. And I found much more than that. Photographic details below.

Photograph of a fig being examined under a dissecting microscope

The wasp was small, like most wasps, so here’s a photograph with an arrow pointing out the position. It was wedged in between some of the involucral bracts just inside the ostiole (opening) of the syconium (the “fruit” that is actually an inverted infructescence). I’m not sure whether the wasp was going in or going out.

Photograph of an opened fig with an arrow showing the location of a dead wasp

Here’s a close-up of the wasp, or at least what’s left of it. The shape and positions of the legs seem to be a good match for Blastophaga psenes, the sole pollinator (I think) of Ficus carica. In particular, the middle femorae are much smaller than the front and hind femorae. And the head is wedge-shaped, another attribute of the family.

The species exists in Turkey and in many other places where figs are grown. E.g., it’s in California because it was deliberately introduced there in 1899. This means, of course, that figs grown in California may have wasps in them, too. I’m just the messenger.

Photograph of a dead fig wasp inside a fig

Below is the dorsal side showing (I think) the quadrate scutellum, another family characteristic. The antennae appear to be folded medially into a streamlined position that I assume is useful for navigating the bract maze. I have more pics on iNaturalist.

Photograph showing the dorsal side of a fig wasp

In a different fig, I found two more wasps of a second species. I don’t have a high confidence in my identification but I think they might be Habrobracon hebetor (Braconidae). This species is a regular inside stored figs because it parasitizes caterpillars that eat dried fruit. This wasp, I’m guessing, oviposited into caterpillar-infested figs after they arrived in California (where Trader Joe’s presumably has a warehouse). I don’t know whether the species occurs in Turkey. I have more pics on iNaturalist.

Photograph of tiny dead wasp next to orange frass

Below is a caterpillar in the same fig as the wasp above. Caterpillars were present in several other figs, too, and they were often accompanied by fungal growth. I don’t have an identification guess but if you recognize it please visit my iNaturalist observation.

Photograph of a dead, shriveled caterpillar

I’m not sure whether it’s a different species, but the cocoons below seem to be lepidopterans, too. Here is the iNaturalist link.

Photograph of two caterpillars inside silk cocoons

Here’s the final type of lepidopteran I found, a pupa. Again, I’m not sure what family it might be in. Here’s the iNaturalist listing. The photograph also shows a good quantity of frass, something I found in many of the figs even when I couldn’t locate a caterpillar. The dark color on the left is from fungal growth.

Photograph of a moth pupa next to fig achenes and black frass

The final insect that turned up is a beetle, which I think might be Carpophilus hemipterus, a species native to Asia but now pretty much everywhere. It’s definitely in California. Here’s my iNaturalist observation if you’d like to weigh in on the identification.

Photograph of black and yellow beetle inside a fig

I’d like to point out that insects are extremely common in stored food so the above doesn’t come as a huge surprise to me. And the figs were clearly labelled “organic”, a term that to me greatly boosts the likelihood that there are organisms inside. Unless you have an allergy to chitin or some other insect component (it happens), inadvertent consumption of arthropods isn’t going to harm you.

What did surprise me was how common fungal growth was in this bag of figs. Below is a photograph of what the fungus usually looked like. Not sure what it is (Aspergillus niger?). Some of them were mildly lit up by 356nm UV light, by the way. I think that’s a bad sign.

Photograph of fungal growth next to achenes inside a fig

But a little research turned up what might be the obvious explanation: wasps that manage to crawl into figs via ostiole can be covered with fungal spores in the same way that they are often covered with pollen (that’s the whole point of fig wasps). Indeed, some fig farmers regularly spray anti-fungals onto figs before the females emerge to prevent them from picking up spores and transmitting them to the next fig. Without such treatment (i.e., at organic farms), it’s not rare to find smuts (Aspergillus spp.), endosepsis (Fusarium spp.), and Alternaria rot. Aside from potentially changing the taste of dried figs, I guess there’s a chance you could get a dose of aflatoxins. There’s research on the issue, even articles on the risk from dried Turkish figs.

When fresh figs start to arrive from California I might sacrifice some for a similar investigation. I’d love to find a fig wasp in better condition so I can photograph it. They are bizarre. But per several sources, many (most?) of the figs in California are produced by plants that don’t need fertilization, so finding one might be a challenge. Still, because fig wasps are naturalized in California, I wouldn’t be surprised if they’d still show up inside those varieties. As a demonstration that wasps are alive and well in California, you can order wasp-laden figs online at FigBid.com (e.g., this listing). Note that you don’t order such figs for eating. They are for placing near your crop of figs so that they can get pollinated. Some of the most delicious varieties of figs need such pollination. And some of the varieties that don’t need figs still develop much tastier fruit when they are pollinated by wasps.

Here’s what the California Fig Advisory Board has to say,

“https://californiafigs.com/faq/#:~:text=I%E2%80%99ve%20heard%20that%20there%20are%20wasps%20in%20figs.%20Is%20this%20true%3F

Next on my to-do list is to find the coffee berry borer (Hypothenemus hampei).

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Insects in the vegetable garden

Here are some photographs I took in June at my allotment in town.

Spotted cucumber beetle (Diabrotica undecimpunctata howardi)

First up is a spotted cucumber beetle (Diabrotica undecimpunctata howardi), perhaps the most common insect in my garden every year. In addition to being defoliators, the beetles are important transmitters of the Erwinia tracheiphila, which causes wilting. I think some of my zucchini fruits might be suffering from this wilt, but I’m not positive. The insect can also eat corn roots during their larval phase (hence its other common name, southern corn rootworm). If any of my corn plants lodge (fall over) I’m going to attempt to find and photograph the little bastards. For a beetle with “cucumber” in the common name it’s stunning how many different types of plants this insect can survive on (per one estimate, over 40 different families). More information on the species can be found at BugGuide.

Mexican bean beetle (Epilachna varivestis)

This is a Mexican bean beetle (Epilachna varivestis) next to some of the damage it presumably caused. If you provoke them they apparently “reflex bleed”, and the blood is laced with a toxic alkaloid (Eisner et al. 1986). I haven’t yet seen their larvae (here‘s an excellent pic) but those have a different alkaloid in their glandular hairs (Attygalle et al. 1993). BugGuide has information on identification, distribution, and life cycle.

Phyllotreta striolata

This is some sort of Phyllotreta, I think, on radish. I spent several hours online trying to identify it to species but got stuck with three options that all are rather similar: Phyllotreta striolata, Phyllotreta zimmermanni, and Phyllotreta liebecki (links go to respective BugGuide pages). But the first option seems the best: “Antennae black, basal 3 segments yellow-brown, 5th segment usually 1/3 longer than 4th, its width 1/4 its length” (BugGuide). Here‘s the iNaturalist observation in the event that an expert is reading this and can help with an ID. These beetles sequester the glucosinolates of their cruciferous hosts (Beran et al. 2014).

Potato stalk borer (Trichobaris trinotata)

This weevil is Trichobaris trinotata, the potato stalk borer. The larvae get inside the stems courtesy of small notches that the female chews prior to oviposition. If any of my potatoes, eggplants, or tomatillo begins to wilt I’m going to dissect the stem in search of the larvae (I’m easily entertained). Adults are easy to ID because of their all-black head and presence of three black spots in between the thorax and elytra. More information is available on BugGuide.

Eggplant flea beetles (Epitrix fuscula)

This is one of hundreds of eggplant flea beetles (Epitrix fuscula) in my garden. In addition to defoliating my eggplants every year they are extremely small and thus hard to photograph and identify. And apparently they might be eating my beets, too, as larvae. BugGuide has cursory information on identification but for more extenstive treatments plus excellent photographs see Deczynski 2014 and Deczynski 2016.

Epitrix brevis

Epitrix brevis is even smaller than the eggplant flea beetle, above, and thus really at the limit of my camera gear and patience. They are all over my tomatillo, slowly skeletonizing some of the leaves through hundreds of tiny excavations like the one in the background of this photograph. Pestiferous, but also rather cute due to their small size. BugGuide has a page on the species but doesn’t have any interesting information. Likely too small.

Lady beetle larvae

These are the larvae of some sort of coccinellid (lady beetle), still hanging around their eggs and perhaps entertaining themselves by eating each other, as one does. I’m wondering whether they might be Harmonia axyridis (Asian lady beetle), an introduced beetle so common that is often a good guess. I need to go back and check on this location (on pole bean leaf) to find later instars or adults. Here’s my iNaturalist observation.

Clouded plant bug (Neurocolpus nubilus)

This menacing insect is a clouded plant bug (Neurocolpus nubilus) and I’ve seen several on my borlotti beans. In perhaps related news, several of my borlotti beans suddenly died this week (early July) and I’m wondering whether this bug is responsible. It’s a known pest of cotton but I can’t find any evidence in the literature that it eats legumes. More details on BugGuide.

Broad-headed sharpshooter (Oncometopia orbona)

This gorgeous leafhopper is a female broad-headed sharpshooter (Oncometopia orbona). Those white spots are chalky deposits (brochosomes) that are often found on females. Females use the substance to coat their eggs, though I’m not sure whether she uses the material from those spots. For the life of me I cannot locate a photograph of eggs protected by this chalk. I gather both males and females of this species (and other leafhoppers and planthoppers) also “anoint” themselves with this goop after each molt to better protect themselves from the elements and from sticky substances (Rakitov 1996). They are really hard to photograph because when they sense your proximity they will quickly move to the other side of the leaf. More on BugGuide.

Swift feather-legged fly (Trichopoda pennipes)

This is a swift feather-legged fly (Trichopoda pennipes), one of my favorite dipterans. I love it because (1) it’s beautiful, (2) not easily spooked, and (3) is a highly motivated parasitoid of squash bugs. I’ve never seen it in action, but they slap eggs right onto squash bugs (and several related bugs), and they do this all day long, sometimes effectively controlling the pest without any need for pesticides. They are so common that if you scroll through pics of squash bugs you’ll see the fly’s eggs regularly (e.g.). Here‘s a nice summary of its life cycle by Susan Mahr (University of Wisconsin). BugGuide.

Condylostylus caudatus

This is a male Condylostylus in the sipho group. My garden has thousands of these flies, all of them likely eating the aphids and other small insects that are present in large numbers. They are extremely skittish and hard to photograph. To make things worse, they also take flight when they detect a flash pulse, so 90% of my shots have only a leg or two. Here’s the iNaturalist observation in case you can help me with the identification. Caleb Scholtens has an excellent guide to the Condylostylus groups on iNaturalist .

Squash vine borer moth (Melittia cucurbitae)

Finally, here’s an early-instar larva of a squash vine borer moth (Melittia cucurbitae) inside a zucchini stem. I found it by examining leaf stems for surface damage caused by oviposition and early feeding by the larva (see pic #3 on my Inaturalist observation to see the damage). These are horrible pests of zucchini and yellow squash, so I tend to wrap the bases of my plants in tinfoil, plus patrol the leaves and fruit stalks for larval damage. The adult, by the way, is stunningly beautiful. BugGuide has identification help, which I recommend checking just to be sure it’s not Melittia calabaza, which looks very similar.

Finally, here’s a non-macro photograph that shows where all these insects are spending their lives, my little allotment at the Scott Arboretum Community Gardens.

Allotment at community vegetable garden

All of the above photographs, plus thousands more, are at https://colinpurrington.smugmug.com.